I recently did a BIOS version upgrade (see information below) and after that version upgrade, grub reports that it does "Adding boot menu entry for UEFI Firmware Settings ...", which is not actually true and no entry was generated, but efibootmgr command works (when given the correct path) "sudo efibootmgr -c --disk /dev/sda --part 1 --label "Manjaro" --loader \\EFI\\Manjaro\\grubx64.efi".
Also after the BIOS upgrade, the boot entry for "Manjaro" was gone, but the entry for "ubuntu" (Linux Mint 20.3) was still available.
Anything else other than the UEFI Boot Entry is correctly placed (meaning that grub is successfully installed on the efi partition and chainloadable, but no uefi boot entry).
System information:
Arch: x86-64 (EFI)
MainBoard: MSI B150M Mortar (from version C.90 (2016) to C.D0 (2018))
System grub is installed on: Manjaro 21.2.6 (efivars are available)
Boot Environment: UEFI + GPT(sda1, fat16)
Secure Boot: false
TPM available: yes 2.0
Boot Mode: UEFI (LEGACY is disabled)
Installed packages:
core/grub 2.06-5
community/grub-btrfs 4.11-2
extra/grub-theme-manjaro 20.2-12
core/efibootmgr 17-2
If more information is needed, I hope to be able to provide it (I just don't know what to provide yet).
grub config:
GRUB_DEFAULT=saved
GRUB_TIMEOUT=5
GRUB_TIMEOUT_STYLE=hidden
GRUB_RECORDFAIL_TIMEOUT=$GRUB_TIMEOUT
GRUB_DISTRIBUTOR="Manjaro"
GRUB_CMDLINE_LINUX_DEFAULT="quiet udev.log_priority=3"
GRUB_CMDLINE_LINUX=""
GRUB_PRELOAD_MODULES="part_gpt part_msdos"
GRUB_TERMINAL_INPUT=console
GRUB_GFXMODE=auto
GRUB_GFXPAYLOAD_LINUX=keep
GRUB_DISABLE_RECOVERY=true
GRUB_DISABLE_OS_PROBER=true
GRUB_COLOR_NORMAL="light-gray/black"
GRUB_COLOR_HIGHLIGHT="green/black"
GRUB_THEME="/usr/share/grub/themes/manjaro/theme.txt"
PS: I don't know if this behavior was present before the BIOS upgrade, because the boot entry was existing before the upgrade but grub was not adding an entry after the upgrade.